1. Field of the Invention
The invention relates to a wholly aromatic polyester film and a process for producing the wholly aromatic polyester film.
2. Description of the Related Art
The homopolymer of 4-hydroxybenzoic acid, which is a wholly aromatic polyester, has excellent heat resistance, abrasion resistance, compression creep resistance, electric insulation and solvent resistance, and its crystalline structure has plate crystal similar to those of solid lubricants such as graphite and molybdenum disulfide; and therefore the polymers excellent in a self lubricity. However, since it is hardly fluidized at a temperature range of 400° C. or less, the polymer cannot be molded by a general molding method and is mainly used for a filler for polytetrafluoroethylene.
Although the wholly aromatic polyester comprising self-condensing monomers (such as 4-hydroxybenzoic acid and 2-hydroxy-6-naphthoic acid) as raw materials of the polyester has excellent properties, it may be insoluble and not fused and it is known that handling is very difficult.